/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.server;

import static com.android.server.input.InputManagerService.SW_HEADPHONE_INSERT;
import static com.android.server.input.InputManagerService.SW_HEADPHONE_INSERT_BIT;
import static com.android.server.input.InputManagerService.SW_LINEOUT_INSERT;
import static com.android.server.input.InputManagerService.SW_LINEOUT_INSERT_BIT;
import static com.android.server.input.InputManagerService.SW_MICROPHONE_INSERT;
import static com.android.server.input.InputManagerService.SW_MICROPHONE_INSERT_BIT;

import android.content.Context;
import android.media.AudioManager;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.os.PowerManager;
import android.os.PowerManager.WakeLock;
import android.os.UEventObserver;
import android.util.Log;
import android.util.Pair;
import android.util.Slog;
import android.view.InputDevice;

import com.android.internal.R;
import com.android.server.input.InputManagerService;
import com.android.server.input.InputManagerService.WiredAccessoryCallbacks;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

/**
 * <p>WiredAccessoryManager monitors for a wired headset on the main board or dock using
 * both the InputManagerService notifyWiredAccessoryChanged interface and the UEventObserver
 * subsystem.
 */
final class WiredAccessoryManager implements WiredAccessoryCallbacks {
    private static final String TAG = WiredAccessoryManager.class.getSimpleName();
    private static final boolean LOG = false;

    private static final int BIT_HEADSET = (1 << 0);
    private static final int BIT_HEADSET_NO_MIC = (1 << 1);
    private static final int BIT_USB_HEADSET_ANLG = (1 << 2);
    private static final int BIT_USB_HEADSET_DGTL = (1 << 3);
    private static final int BIT_HDMI_AUDIO = (1 << 4);
    private static final int BIT_LINEOUT = (1 << 5);
    private static final int SUPPORTED_HEADSETS = (BIT_HEADSET | BIT_HEADSET_NO_MIC |
            BIT_USB_HEADSET_ANLG | BIT_USB_HEADSET_DGTL |
            BIT_HDMI_AUDIO | BIT_LINEOUT);

    private static final String NAME_H2W = "h2w";
    private static final String NAME_USB_AUDIO = "usb_audio";
    private static final String NAME_HDMI_AUDIO = "hdmi_audio";
    private static final String NAME_DP_AUDIO = "soc:qcom,msm-ext-disp";
    // within a device, a single stream supports DP
    private static final String[] DP_AUDIO_CONNS = {
            NAME_DP_AUDIO + "/3/1",
            NAME_DP_AUDIO + "/2/1",
            NAME_DP_AUDIO + "/1/1",
            NAME_DP_AUDIO + "/0/1",
            NAME_DP_AUDIO + "/3/0",
            NAME_DP_AUDIO + "/2/0",
            NAME_DP_AUDIO + "/1/0",
            NAME_DP_AUDIO + "/0/0"
    };

    private static final String NAME_HDMI = "hdmi";
    private static final String INTF_DP = "DP";
    private static final String INTF_HDMI = "HDMI";
    private static final int MSG_NEW_DEVICE_STATE = 1;
    private static final int MSG_SYSTEM_READY = 2;

    private final Object mLock = new Object();

    private final WakeLock mWakeLock;  // held while there is a pending route change
    private final AudioManager mAudioManager;

    private int mHeadsetState;
    private int mDpCount;
    private String mDetectedIntf = INTF_DP;
    private int mSwitchValues;

    private final WiredAccessoryObserver mObserver;
    private final WiredAccessoryExtconObserver mExtconObserver;
    private final InputManagerService mInputManager;

    private final boolean mUseDevInputEventForAudioJack;

    public WiredAccessoryManager(Context context, InputManagerService inputManager) {
        PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
        mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "WiredAccessoryManager");
        mWakeLock.setReferenceCounted(false);
        mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
        mInputManager = inputManager;

        mUseDevInputEventForAudioJack =
                context.getResources().getBoolean(R.bool.config_useDevInputEventForAudioJack);

        mExtconObserver = new WiredAccessoryExtconObserver();
        mObserver = new WiredAccessoryObserver();
    }

    private void onSystemReady() {
        if (mUseDevInputEventForAudioJack) {
            int switchValues = 0;
            if (mInputManager.getSwitchState(-1, InputDevice.SOURCE_ANY, SW_HEADPHONE_INSERT)
                    == 1) {
                switchValues |= SW_HEADPHONE_INSERT_BIT;
            }
            if (mInputManager.getSwitchState(-1, InputDevice.SOURCE_ANY, SW_MICROPHONE_INSERT)
                    == 1) {
                switchValues |= SW_MICROPHONE_INSERT_BIT;
            }
            if (mInputManager.getSwitchState(-1, InputDevice.SOURCE_ANY, SW_LINEOUT_INSERT) == 1) {
                switchValues |= SW_LINEOUT_INSERT_BIT;
            }
            notifyWiredAccessoryChanged(0, switchValues,
                    SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT | SW_LINEOUT_INSERT_BIT);
        }


        if (ExtconUEventObserver.extconExists() && mExtconObserver.uEventCount() > 0 && false) {
            if (mUseDevInputEventForAudioJack) {
                Log.w(TAG, "Both input event and extcon are used for audio jack,"
                        + " please just choose one.");
            }
            mExtconObserver.init();
        } else {
            mObserver.init();
        }
    }

    @Override
    public void notifyWiredAccessoryChanged(long whenNanos, int switchValues, int switchMask) {
        if (LOG) {
            Slog.v(TAG, "notifyWiredAccessoryChanged: when=" + whenNanos
                    + " bits=" + switchCodeToString(switchValues, switchMask)
                    + " mask=" + Integer.toHexString(switchMask));
        }

        synchronized (mLock) {
            int headset;
            mSwitchValues = (mSwitchValues & ~switchMask) | switchValues;
            switch (mSwitchValues &
                    (SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT | SW_LINEOUT_INSERT_BIT)) {
                case 0:
                    headset = 0;
                    break;

                case SW_HEADPHONE_INSERT_BIT:
                    headset = BIT_HEADSET_NO_MIC;
                    break;

                case SW_LINEOUT_INSERT_BIT:
                    headset = BIT_LINEOUT;
                    break;

                case SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT:
                    headset = BIT_HEADSET;
                    break;

                case SW_MICROPHONE_INSERT_BIT:
                    headset = BIT_HEADSET;
                    break;

                default:
                    headset = 0;
                    break;
            }

            updateLocked(NAME_H2W, "",
                    (mHeadsetState & ~(BIT_HEADSET | BIT_HEADSET_NO_MIC | BIT_LINEOUT)) | headset);
        }
    }

    @Override
    public void systemReady() {
        synchronized (mLock) {
            mWakeLock.acquire();

            Message msg = mHandler.obtainMessage(MSG_SYSTEM_READY, 0, 0, null);
            mHandler.sendMessage(msg);
        }
    }

    /**
     * Compare the existing headset state with the new state and pass along accordingly. Note
     * that this only supports a single headset at a time. Inserting both a usb and jacked headset
     * results in support for the last one plugged in. Similarly, unplugging either is seen as
     * unplugging all.
     *
     * For Display port allow up to two connections.
     * Block display port request if HDMI already connected and vice versa.
     *
     * @param newName  One of the NAME_xxx variables defined above.
     * @param newState 0 or one of the BIT_xxx variables defined above.
     */
    private void updateLocked(String newName, String address, int newState) {
        // Retain only relevant bits
        int headsetState = newState & SUPPORTED_HEADSETS;
        int newDpState = newState & BIT_HDMI_AUDIO;
        int usb_headset_anlg = headsetState & BIT_USB_HEADSET_ANLG;
        int usb_headset_dgtl = headsetState & BIT_USB_HEADSET_DGTL;
        int h2w_headset = headsetState & (BIT_HEADSET | BIT_HEADSET_NO_MIC | BIT_LINEOUT);
        boolean h2wStateChange = true;
        boolean usbStateChange = true;
        boolean dpBitState = (mHeadsetState & BIT_HDMI_AUDIO) > 0;
        boolean dpCountState = mDpCount != 0;
        if (LOG) {
            Slog.v(TAG, "newName=" + newName
                    + " newState=" + newState
                    + " headsetState=" + headsetState
                    + " prev headsetState=" + mHeadsetState
                    + " num of active dp conns= " + mDpCount);
        }

        if (mHeadsetState == headsetState && !newName.startsWith(NAME_DP_AUDIO)) {
            Log.e(TAG, "No state change.");
            return;
        }

        // reject all suspect transitions: only accept state changes from:
        // - a: 0 headset to 1 headset
        // - b: 1 headset to 0 headset
        if (h2w_headset == (BIT_HEADSET | BIT_HEADSET_NO_MIC | BIT_LINEOUT)) {
            Log.e(TAG, "Invalid combination, unsetting h2w flag");
            h2wStateChange = false;
        }
        // - c: 0 usb headset to 1 usb headset
        // - d: 1 usb headset to 0 usb headset
        if (usb_headset_anlg == BIT_USB_HEADSET_ANLG && usb_headset_dgtl == BIT_USB_HEADSET_DGTL) {
            Log.e(TAG, "Invalid combination, unsetting usb flag");
            usbStateChange = false;
        }
        if (!h2wStateChange && !usbStateChange) {
            Log.e(TAG, "invalid transition, returning ...");
            return;
        }

        if (newName.startsWith(NAME_DP_AUDIO)) {
            if ((newDpState > 0) && (mDpCount < DP_AUDIO_CONNS.length)
                    && (dpBitState == dpCountState)) {
                // Allow DP0 if no HDMI previously connected.
                // Allow second request only if DP connected previously.
                mDpCount++;
            } else if ((newDpState == 0) && (mDpCount > 0)) {
                mDpCount--;
            } else {
                Log.e(TAG, "No state change for DP.");
                return;
            }
        }

        mWakeLock.acquire();

        Log.i(TAG, "MSG_NEW_DEVICE_STATE");
        // Send a combined name, address string separated by |
        Message msg;
        if (newName.startsWith(NAME_DP_AUDIO)) {
            int pseudoHeadsetState = mHeadsetState;
            if (dpBitState && (newDpState != 0)) {
                // One DP already connected, so allow request to connect second.
                pseudoHeadsetState = mHeadsetState & (~BIT_HDMI_AUDIO);
            }
            msg = mHandler.obtainMessage(MSG_NEW_DEVICE_STATE, headsetState,
                    pseudoHeadsetState, NAME_DP_AUDIO + "/" + address);

            if ((headsetState == 0) && (mDpCount != 0)) {
                // Atleast one DP is connected, so keep mHeadsetState's DP bit set.
                headsetState = headsetState | BIT_HDMI_AUDIO;
            }
        } else {
            msg = mHandler.obtainMessage(MSG_NEW_DEVICE_STATE, headsetState,
                    mHeadsetState, newName + "/" + address);
        }
        mHandler.sendMessage(msg);

        mHeadsetState = headsetState;
    }

    private final Handler mHandler = new Handler(Looper.myLooper(), null, true) {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_NEW_DEVICE_STATE:
                    setDevicesState(msg.arg1, msg.arg2, (String) msg.obj);
                    mWakeLock.release();
                    break;
                case MSG_SYSTEM_READY:
                    onSystemReady();
                    mWakeLock.release();
                    break;
            }
        }
    };

    private void setDevicesState(
            int headsetState, int prevHeadsetState, String headsetNameAddr) {
        synchronized (mLock) {
            int allHeadsets = SUPPORTED_HEADSETS;
            for (int curHeadset = 1; allHeadsets != 0; curHeadset <<= 1) {
                if ((curHeadset & allHeadsets) != 0) {
                    setDeviceStateLocked(curHeadset, headsetState, prevHeadsetState,
                            headsetNameAddr);
                    allHeadsets &= ~curHeadset;
                }
            }
        }
    }

    private void setDeviceStateLocked(int headset,
            int headsetState, int prevHeadsetState, String headsetNameAddr) {
        if ((headsetState & headset) != (prevHeadsetState & headset)) {
            int outDevice = 0;
            int inDevice = 0;
            int state;

            if ((headsetState & headset) != 0) {
                state = 1;
            } else {
                state = 0;
            }

            if (headset == BIT_HEADSET) {
                outDevice = AudioManager.DEVICE_OUT_WIRED_HEADSET;
                inDevice = AudioManager.DEVICE_IN_WIRED_HEADSET;
            } else if (headset == BIT_HEADSET_NO_MIC) {
                outDevice = AudioManager.DEVICE_OUT_WIRED_HEADPHONE;
            } else if (headset == BIT_LINEOUT) {
                outDevice = AudioManager.DEVICE_OUT_LINE;
            } else if (headset == BIT_USB_HEADSET_ANLG) {
                outDevice = AudioManager.DEVICE_OUT_ANLG_DOCK_HEADSET;
            } else if (headset == BIT_USB_HEADSET_DGTL) {
                outDevice = AudioManager.DEVICE_OUT_DGTL_DOCK_HEADSET;
            } else if (headset == BIT_HDMI_AUDIO) {
                outDevice = AudioManager.DEVICE_OUT_HDMI;
            } else {
                Slog.e(TAG, "setDeviceState() invalid headset type: " + headset);
                return;
            }

            if (LOG) {
                Slog.v(TAG, "headsetNameAddr: " + headsetNameAddr +
                        (state == 1 ? " connected" : " disconnected"));
            }

            String[] hs = headsetNameAddr.split("/");
            if (outDevice != 0) {
                mAudioManager.setWiredDeviceConnectionState(outDevice, state,
                        (hs.length > 1 ? hs[1] : ""), hs[0]);
            }
            if (inDevice != 0) {
                mAudioManager.setWiredDeviceConnectionState(inDevice, state,
                        (hs.length > 1 ? hs[1] : ""), hs[0]);
            }
        }
    }

    private String switchCodeToString(int switchValues, int switchMask) {
        StringBuilder sb = new StringBuilder();
        if ((switchMask & SW_HEADPHONE_INSERT_BIT) != 0 &&
                (switchValues & SW_HEADPHONE_INSERT_BIT) != 0) {
            sb.append("SW_HEADPHONE_INSERT ");
        }
        if ((switchMask & SW_MICROPHONE_INSERT_BIT) != 0 &&
                (switchValues & SW_MICROPHONE_INSERT_BIT) != 0) {
            sb.append("SW_MICROPHONE_INSERT");
        }
        return sb.toString();
    }

    class WiredAccessoryObserver extends UEventObserver {
        private final List<UEventInfo> mUEventInfo;
        private List<String> mDevPath = new ArrayList<String>();

        public WiredAccessoryObserver() {
            mUEventInfo = makeObservedUEventList();
        }

        void init() {
            synchronized (mLock) {
                if (LOG) Slog.v(TAG, "init()");
                char[] buffer = new char[1024];

                for (int i = 0; i < mUEventInfo.size(); ++i) {
                    UEventInfo uei = mUEventInfo.get(i);
                    try {
                        int curState;
                        String switchStatePath = uei.getSwitchStatePath();
                        FileReader file = new FileReader(switchStatePath);
                        int len = file.read(buffer, 0, 1024);
                        file.close();
                        curState = Integer.parseInt(
                                (new String(buffer, 0, len).replaceAll("\\D+","")).trim());

                        if (curState > 0) {
                            int index = switchStatePath.lastIndexOf(".");
                            if (switchStatePath.substring(index + 1, index + 2).equals("1")) {
                                mDetectedIntf = INTF_HDMI;
                            }
                            updateStateLocked(uei.getDevPath(), uei.getDevName(), curState);
                        }
                    } catch (FileNotFoundException e) {
                        Slog.w(TAG, uei.getSwitchStatePath() +
                                " not found while attempting to determine initial switch state");
                    } catch (Exception e) {
                        Slog.e(TAG, "Error while attempting to determine initial switch state for "
                                + uei.getDevName(), e);
                    }
                }
            }

            // At any given time accessories could be inserted
            // one on the board, one on the dock and one on HDMI:
            // observe three UEVENTs
            for (int i = 0; i < mUEventInfo.size(); ++i) {
                UEventInfo uei = mUEventInfo.get(i);
                String devPath = uei.getDevPath();

                if (mDevPath.contains(devPath))
                    continue;

                startObserving("DEVPATH=" + uei.getDevPath());
                mDevPath.add(devPath);
            }
        }

        private List<UEventInfo> makeObservedUEventList() {
            List<UEventInfo> retVal = new ArrayList<UEventInfo>();
            UEventInfo uei;

            // Monitor h2w
            if (!mUseDevInputEventForAudioJack) {
                uei = new UEventInfo(NAME_H2W, BIT_HEADSET, BIT_HEADSET_NO_MIC, BIT_LINEOUT);
                if (uei.checkSwitchExists()) {
                    retVal.add(uei);
                } else {
                    Slog.w(TAG, "This kernel does not have wired headset support");
                }
            }

            // Monitor USB
            uei = new UEventInfo(NAME_USB_AUDIO, BIT_USB_HEADSET_ANLG, BIT_USB_HEADSET_DGTL, 0);
            if (uei.checkSwitchExists()) {
                retVal.add(uei);
            } else {
                Slog.w(TAG, "This kernel does not have usb audio support");
            }

            // Monitor HDMI
            //
            // If the kernel has support for the "hdmi_audio" switch, use that.  It will be
            // signalled only when the HDMI driver has a video mode configured, and the downstream
            // sink indicates support for audio in its EDID.
            //
            // If the kernel does not have an "hdmi_audio" switch, just fall back on the older
            // "hdmi" switch instead.
            uei = new UEventInfo(NAME_HDMI_AUDIO, BIT_HDMI_AUDIO, 0, 0);
            if (uei.checkSwitchExists()) {
                retVal.add(uei);
            } else {
                uei = new UEventInfo(NAME_HDMI, BIT_HDMI_AUDIO, 0, 0);
                if (uei.checkSwitchExists()) {
                    retVal.add(uei);
                } else {
                    Slog.w(TAG, "This kernel does not have HDMI audio support");
                }
            }

            for (String conn : DP_AUDIO_CONNS) {
                // Monitor DisplayPort
                if (LOG) {
                    Slog.v(TAG, "Monitor DP conn " + conn);
                }
                uei = new UEventInfo(conn, BIT_HDMI_AUDIO, 0, 0);
                if (uei.checkSwitchExists()) {
                    retVal.add(uei);
                } else {
                    Slog.w(TAG, "Conn " + conn + " does not have DP audio support");
                }
            }

            return retVal;
        }

        @Override
        public void onUEvent(UEventObserver.UEvent event) {
            String devPath = event.get("DEVPATH");
            String name = event.get("NAME");
            int state = 0;

            if (name == null) {
                name = event.get("SWITCH_NAME");
            }

            try {
                if (name.startsWith(NAME_DP_AUDIO)) {
                    String stateStr = event.get("STATE");
                    int offset = 0;
                    int length = stateStr.length();

                    // parse DP=1\nHDMI=1\0
                    while (offset < length) {
                        int equals = stateStr.indexOf('=', offset);

                        if (equals > offset) {
                            String intfName = stateStr.substring(offset, equals);

                            if (intfName.equals("DP") || intfName.equals("HDMI")) {
                                state = Integer.parseInt(
                                        stateStr.substring(equals + 1, equals + 2));
                                if (state == 1) {
                                    mDetectedIntf = intfName;
                                    break;
                                }
                            }
                        }

                        offset = equals + 3;
                    }
                } else {
                    state = Integer.parseInt(event.get("SWITCH_STATE"));
                }
            } catch (NumberFormatException e) {
                Slog.i(TAG, "couldn't get state from event, checking node");

                for (int i = 0; i < mUEventInfo.size(); ++i) {
                    UEventInfo uei = mUEventInfo.get(i);

                    if (name.equals(uei.getDevName())) {
                        char[] buffer = new char[1024];
                        int len = 0;

                        try {
                            FileReader file = new FileReader(uei.getSwitchStatePath());
                            len = file.read(buffer, 0, 1024);
                            file.close();
                        } catch (FileNotFoundException e1) {
                            Slog.e(TAG, "file not found");
                            break;
                        } catch (Exception e11) {
                            Slog.e(TAG, "onUEvent exception", e11);
                        }

                        try {
                            state = Integer.parseInt((new String(buffer, 0, len)).trim());
                        } catch (NumberFormatException e2) {
                            Slog.e(TAG, "could not convert to number");
                            break;
                        }
                        break;
                    }
                }
            }

            synchronized (mLock) {
                updateStateLocked(devPath, name, state);
            }
        }

        private void updateStateLocked(String devPath, String name, int state) {
            for (int i = 0; i < mUEventInfo.size(); ++i) {
                UEventInfo uei = mUEventInfo.get(i);
                if (devPath.equals(uei.getDevPath())) {
                    if (state == 1 && mDpCount > 0) {
                        uei.setStreamIndex(mDpCount);
                    }

                    if (state == 1) {
                        int newControllerIdx = (mDetectedIntf.equals(INTF_DP)) ? 0 : 1;
                        uei.setCableIndex(newControllerIdx);
                    }
                    updateLocked(name, uei.getDevAddress(),
                            uei.computeNewHeadsetState(mHeadsetState, state));
                    return;
                }
            }
        }

        private final class UEventInfo {
            private final String mDevName;
            private String mDevAddress;
            private final int mState1Bits;
            private final int mState2Bits;
            private final int mStateNbits;
            private int mDevIndex;
            private int mCableIndex;

            public UEventInfo(String devName, int state1Bits, int state2Bits, int stateNbits) {
                mDevName = devName;
                mDevAddress = "controller=0;stream=0";
                mState1Bits = state1Bits;
                mState2Bits = state2Bits;
                mStateNbits = stateNbits;

                mDevIndex = -1;
                mCableIndex = -1;

                if (mDevName.startsWith(NAME_DP_AUDIO)) {
                    int idx = mDevName.indexOf("/");
                    if (idx != -1) {
                        int idx2 = mDevName.indexOf("/", idx + 1);
                        assert(idx2 != -1);
                        int dev = Integer.parseInt(mDevName.substring(idx + 1, idx2));
                        int cable = Integer.parseInt(mDevName.substring(idx2 + 1));
                        if (LOG) {
                            Slog.v(TAG, "UEvent dev address " + mDevAddress);
                        }
                        checkDevIndex(dev);
                        checkCableIndex(cable);
                    }
                }
            }

            private void checkDevIndex(int devIndex) {
                int index = 0;
                char[] buffer = new char[1024];

                while (true) {
                    String devPath = String.format(Locale.US,
                            "/sys/devices/platform/soc/%s/extcon/extcon%d/name",
                            NAME_DP_AUDIO, devIndex);
                    if (LOG) {
                        Slog.v(TAG, "checkDevIndex " + devPath);
                    }

                    File f = new File(devPath);
                    if (!f.exists()) {
                        Slog.e(TAG, "file " + devPath + " not found");
                        break;
                    }

                    try {
                        FileReader file = new FileReader(f);
                        int len = file.read(buffer, 0, 1024);
                        file.close();

                        String devName = (new String(buffer, 0, len)).trim();
                        if (devName.startsWith(NAME_DP_AUDIO) && index == devIndex) {
                            mDevIndex = devIndex;
                            break;
                        } else {
                            index++;
                        }
                    } catch (Exception e) {
                        Slog.e(TAG, "checkDevIndex exception", e);
                        break;
                    }
                }
            }

            private void checkCableIndex(int cableIndex) {
                if (mDevIndex == -1) {
                    return;
                }
                int index = 0;
                char[] buffer = new char[1024];

                while (true) {
                    String cablePath = String.format(Locale.US,
                            "/sys/devices/platform/soc/%s/extcon/extcon%d/cable.%d/name",
                            NAME_DP_AUDIO, mDevIndex, index);
                    if (LOG) {
                        Slog.v(TAG, "checkCableIndex " + cablePath);
                    }

                    File f = new File(cablePath);
                    if (!f.exists()) {
                        Slog.e(TAG, "file " + cablePath + " not found");
                        break;
                    }

                    try {
                        FileReader file = new FileReader(f);
                        int len = file.read(buffer, 0, 1024);
                        file.close();

                        String cableName = (new String(buffer, 0, len)).trim();
                        if (cableName.equals("HDMI") && index == cableIndex) {
                            mCableIndex = index;
                            break;
                        } else if (cableName.equals("DP") && index == cableIndex) {
                            mCableIndex = index;
                            break;
                        } else {
                            index++;
                        }
                    } catch (Exception e) {
                        Slog.e(TAG, "checkCableIndex exception", e);
                        break;
                    }
                }
            }

            public void setStreamIndex(int streamIndex) {
                int index1 = mDevAddress.indexOf("=");
                int index2 = mDevAddress.indexOf("=", index1 + 1);

                String allExceptStreamIdx = mDevAddress.substring(0, index2 + 1);
                mDevAddress = allExceptStreamIdx + String.valueOf(streamIndex);
            }

            public void setCableIndex(int cableIndex) {
                int index = mDevAddress.indexOf("=");
                String changeControllerIdx = mDevAddress.substring(0, index + 1) + cableIndex
                        + mDevAddress.substring(index + 2);
                mDevAddress = changeControllerIdx;
            }

            public String getDevName() {
                return mDevName;
            }

            public String getDevAddress() {
                return mDevAddress;
            }

            public String getDevPath() {
                if (mDevName.startsWith(NAME_DP_AUDIO)) {
                    return String.format(Locale.US,
                            "/devices/platform/soc/%s/extcon/extcon%d",
                            NAME_DP_AUDIO, mDevIndex);
                }
                return String.format(Locale.US, "/devices/virtual/switch/%s", mDevName);
            }

            public String getSwitchStatePath() {
                if (mDevName.startsWith(NAME_DP_AUDIO)) {
                    return String.format(Locale.US,
                            "/sys/devices/platform/soc/%s/extcon/extcon%d/cable.%d/state",
                            NAME_DP_AUDIO, mDevIndex, mCableIndex);
                }
                return String.format(Locale.US, "/sys/class/switch/%s/state", mDevName);
            }

            public boolean checkSwitchExists() {
                File f = new File(getSwitchStatePath());
                return f.exists();
            }

            public int computeNewHeadsetState(int headsetState, int switchState) {
                int preserveMask = ~(mState1Bits | mState2Bits | mStateNbits);
                int setBits = ((switchState == 1) ? mState1Bits :
                        ((switchState == 2) ? mState2Bits :
                                ((switchState == mStateNbits) ? mStateNbits : 0)));

                return ((headsetState & preserveMask) | setBits);
            }
        }
    }

    private class WiredAccessoryExtconObserver extends ExtconStateObserver<Pair<Integer, Integer>> {
        private final List<ExtconInfo> mExtconInfos;

        WiredAccessoryExtconObserver() {
            mExtconInfos = ExtconInfo.getExtconInfoForTypes(new String[] {
                    ExtconInfo.EXTCON_HEADPHONE,
                    ExtconInfo.EXTCON_MICROPHONE,
                    ExtconInfo.EXTCON_HDMI,
                    ExtconInfo.EXTCON_LINE_OUT,
            });
        }

        private void init() {
            for (ExtconInfo extconInfo : mExtconInfos) {
                Pair<Integer, Integer> state = null;
                try {
                    state = parseStateFromFile(extconInfo);
                } catch (FileNotFoundException e) {
                    Slog.w(TAG, extconInfo.getStatePath()
                            + " not found while attempting to determine initial state", e);
                } catch (IOException e) {
                    Slog.e(
                            TAG,
                            "Error reading " + extconInfo.getStatePath()
                                    + " while attempting to determine initial state",
                            e);
                }
                if (state != null) {
                    updateState(extconInfo, extconInfo.getName(), state);
                }
                if (LOG) Slog.d(TAG, "observing " + extconInfo.getName());
                startObserving(extconInfo);
            }

        }

        public int uEventCount() {
            return mExtconInfos.size();
        }

        @Override
        public Pair<Integer, Integer> parseState(ExtconInfo extconInfo, String status) {
            if (LOG) Slog.v(TAG, "status  " + status);
            int[] maskAndState = {0, 0};
            // extcon event state changes from kernel4.9
            // new state will be like STATE=MICROPHONE=1\nHEADPHONE=0
            if (extconInfo.hasCableType(ExtconInfo.EXTCON_HEADPHONE)) {
                updateBit(maskAndState, BIT_HEADSET_NO_MIC, status, ExtconInfo.EXTCON_HEADPHONE);
            }
            if (extconInfo.hasCableType(ExtconInfo.EXTCON_MICROPHONE)) {
                updateBit(maskAndState, BIT_HEADSET, status, ExtconInfo.EXTCON_MICROPHONE);
            }
            if (extconInfo.hasCableType(ExtconInfo.EXTCON_HDMI)) {
                updateBit(maskAndState, BIT_HDMI_AUDIO, status, ExtconInfo.EXTCON_HDMI);
            }
            if (extconInfo.hasCableType(ExtconInfo.EXTCON_LINE_OUT)) {
                updateBit(maskAndState, BIT_LINEOUT, status, ExtconInfo.EXTCON_LINE_OUT);
            }
            if (LOG) Slog.v(TAG, "mask " + maskAndState[0] + " state " + maskAndState[1]);
            return Pair.create(maskAndState[0], maskAndState[1]);
        }

        @Override
        public void updateState(ExtconInfo extconInfo, String name,
                Pair<Integer, Integer> maskAndState) {
            synchronized (mLock) {
                int mask = maskAndState.first;
                int state = maskAndState.second;
                updateLocked(name, "", mHeadsetState & ~(mask & ~state) | (mask & state));
                return;
            }
        }
    }

    /**
     * Updates the mask bit at {@code position} to 1 and the state bit at {@code position} to true
     * if {@code name=1}  or false if {}@code name=0} is contained in {@code state}.
     */
    private static void updateBit(int[] maskAndState, int position, String state, String name) {
        maskAndState[0] |= position;
        if (state.contains(name + "=1")) {
            maskAndState[0] |= position;
            maskAndState[1] |= position;
        } else if (state.contains(name + "=0")) {
            maskAndState[0] |= position;
            maskAndState[1] &= ~position;
        }
    }
}
